Systems for processing one or more semiconductor devices, and related methods

ABSTRACT

A system for fabricating a semiconductor device structure includes a tool comprising a chamber and a platform within the chamber configured to receive a semiconductor device structure thereon. The tool further includes a heating and cooling system in operable communication with the platform and configured to control a temperature of the platform. The heating and cooling system comprises a cooling system including a cold tank for containing a cold thermal transfer fluid, the cold tank configured to be in fluid communication with the platform, thermal transfer fluid supply piping, and thermal transfer fluid return piping, a heating system including a hot tank for containing a hot thermal transfer fluid having a higher temperature than the cold thermal transfer fluid, the hot tank configured to be in fluid communication with the platform, the thermal transfer fluid supply piping, and the thermal transfer fluid return piping, and at least one temporary storage tank configured to receive at least some of the cold thermal transfer fluid or the hot thermal transfer fluid from at least the thermal transfer fluid return piping after switching a thermal load from the platform from one of the cooling system or the heating system to the other of the cooling system or the heating system. Related methods and tools are disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/976,623, filed May 10, 2018, and titled “TOOLS AND SYSTEMS FORPROCESSING A SEMICONDUCTOR DEVICE STRUCTURE, AND RELATED METHODS,” thedisclosure of which is hereby incorporated herein in its entirety bythis reference.

TECHNICAL FIELD

Embodiments disclosed herein relate to tools and systems for processingsemiconductor device structures, and to related methods. Moreparticularly, embodiments of the disclosure relate to tools and systemsfor processing semiconductor device structures, such systems including aheating and cooling apparatus comprising at least a hot tank and a coldtank and configured to maintain a desired temperature of a semiconductorsubstrate such as a semiconductor wafer in a tool within desiredtolerances and time frames when heating and cooling requirements of thetool change, and to related methods of maintaining the desiredtemperature.

BACKGROUND

Fabrication of semiconductor devices includes, among other things,forming materials on a semiconductor substrate and patterning thematerials to form discrete features isolated from each other by, forexample, dielectric materials. Forming the materials on the substratemay include depositing one or more materials on the substrate by atomiclayer deposition, chemical vapor deposition, physical vapor deposition,or other methods. Forming the materials on the substrate may includemaintaining and altering suitable conditions, such as temperature andpressure, proximate the semiconductor substrate, which may be located ina tool, such as a deposition chamber.

Patterning the materials on the substrate may be performed by etching,such as dry etching. Dry etching may include exposing the materials onthe substrate to one or more dry etch gases (e.g., plasmas) in an etchtool. In some instances, the etch tool is maintained at a relatively lowtemperature (e.g., below about −50° C.) during patterning of thesemiconductor wafer. After patterning the semiconductor wafer, it may bedesired to clean the etch tool, which often includes increasing atemperature of the etch tool. Each act in the fabrication ofsemiconductor device may include maintaining a desired temperature ofthe semiconductor wafer in the etch tool within desired tolerances andtime frames. However, as the temperature difference between the hot andcold requirements of the tool increases, the tool may struggle tomaintain a desired temperature within the tool within a suitable timeframe. For example, in some etch tools, when the temperature of the etchtool is changed by a temperature greater than about, for example, 50°C., the thermal load on the chiller may be too large to adequatelycontrol the temperature within a desired time.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified schematic of a tool for fabricating asemiconductor wafer, in accordance with embodiments of the disclosure;

FIG. 2 is a simplified schematic of a heating and cooling apparatus ofthe tool, in accordance with embodiments of the disclosure;

FIG. 3 is a simplified flow diagram of a method of maintaining atemperature of a tool used during processing of a semiconductor wafer,in accordance with embodiments of the disclosure;

FIG. 4 is a simplified schematic of a heating and cooling apparatus ofthe tool, in accordance with other embodiments of the disclosure; and

FIG. 5 is a simplified flow diagram of a method of maintaining atemperature of a tool used during processing of a semiconductor wafer,in accordance with other embodiments of the disclosure.

DETAILED DESCRIPTION

The illustrations included herewith are not meant to be actual views ofany particular systems, semiconductor structures, or semiconductordevices, but are merely idealized representations that are employed todescribe embodiments herein. Elements and features common betweenfigures may retain the same numerical designation except that, for easeof following the description, for the most part, reference numeralsbegin with the number of the drawing on which the elements areintroduced or most fully described.

The following description provides specific details, such as materialtypes, material thicknesses, and processing conditions in order toprovide a thorough description of embodiments described herein. However,a person of ordinary skill in the art will understand that theembodiments disclosed herein may be practiced without employing thesespecific details. Indeed, the embodiments may be practiced inconjunction with conventional fabrication techniques employed in thesemiconductor industry. In addition, the description provided hereindoes not form a complete description of a semiconductor devicestructure, a tool used during processing of a semiconductor devicestructure, or a complete description of a process flow for fabricating asemiconductor device. The structures described below do not formcomplete semiconductor device structures, or tools or systems forprocessing semiconductor device structures. Only those process acts andstructures necessary to understand the embodiments described herein aredescribed in detail below. Additional acts to form a completesemiconductor device structure or a tool or system for processing asemiconductor device structure may be performed by conventionaltechniques.

As used herein, the term “piping” means and includes pipe, conduits,tubes, or any means for transmitting (e.g., conveying) one or moresubstances from one location to another. Piping may include suitableconduits, fittings, valves, flanges, or other components for forming asealed system for transmitting the one or more substances.

According to embodiments disclosed herein, a semiconductor devicestructure such as semiconductor wafer or other semiconductor substrate(including, for example, one or more semiconductor devices) isfabricated in a wafer processing tool, such as, but not limited to, anetch tool. Processing of a semiconductor wafer may include operating theetch tool at a wide range of temperatures, such as when thesemiconductor wafer is patterned or when the etch tool is cleaned. Forexample, during processing of the semiconductor wafer, the etch tool maybe repeatedly operated at temperatures as low as about −70° C. duringpatterning of the semiconductor wafer and temperatures as high as about70° C. during cleaning of the etch tool, during different patterningacts, or both. The etch tool may include a wafer stage (e.g., anelectrostatic chuck) on which the semiconductor wafer may be disposedduring processing of the semiconductor wafer. The etch tool may includea heating and cooling apparatus in operable communication with at leasta portion of the etch tool (such as the electrostatic chuck) configuredto control a temperature of the at least a portion of the etch tool. Insome embodiments, the heating and cooling apparatus is in operablecommunication with the electrostatic chuck and is configured to heat andcool the electrostatic chuck to a desired temperature. In other waferprocessing tools, the wafer stage may not comprise an electrostaticchuck, and for purposes of the present disclosure, the structure to beheated and cooled according to embodiments of the disclosure may begenerally referred to as a “platform.” The term “platform” does not,however, require or imply that the platform structure is configured forsupport of a semiconductor device structure thereon.

The heating and cooling apparatus may include a hot tank containing ahot thermal transfer fluid and a cold tank containing a relatively coldthermal transfer fluid. As used herein, although the hot tank may bedescribed as “containing” the hot thermal transfer fluid and the coldtank may be described as “containing” the cold thermal transfer fluid,the disclosure is not so limited. It will be understood that the hotthermal transfer fluid or the cold thermal transfer fluid may not becontained within the respective hot tank and cold tank. Rather, the hottank and cold tank may be configured to hold such fluids, even if suchfluids are not physically contained in the tanks. A temperaturedifference between the hot thermal transfer fluid and the cold thermaltransfer fluid may be as much as about 140° C. (e.g., as much as about160° C., as much as about 180° C., as much as about 200° C., as much asabout 250° C., or even as much as about 300° C.). During some portionsof processing of the semiconductor wafer, it may be desirable tomaintain the semiconductor wafer at an elevated temperature (e.g., about70° C.) and during other portions of processing of the semiconductorwafer, it may be desirable to maintain the semiconductor wafer at alower temperature (e.g., −70° C.). The temperature of the semiconductorwafer may be controlled by disposing the semiconductor wafer on aplatform (e.g., an electrostatic chuck) and controlling a temperature ofthe electrostatic chuck. Accordingly, during processing of thesemiconductor wafer, it may be desired to repeatedly switch thetemperature of the electrostatic chuck from an elevated temperature to alower temperature and back from the lower temperature to the elevatedtemperature, such as between various etching acts, cleaning acts,deposition acts, or other acts. Accordingly, the heating and coolingapparatus may be configured to receive a thermal load from theelectrostatic chuck to maintain one or more desired temperatures of theelectrostatic chuck. The hot thermal transfer fluid may be circulatedfrom the hot tank to the electrostatic chuck, from the electrostaticchuck through thermal transfer fluid return piping, and back to the hottank to heat the electrostatic chuck to a desired elevated temperatureand the cold thermal transfer fluid may be circulated from the cold tankto the electrostatic chuck, from the electrostatic chuck to the thermaltransfer fluid return piping, and back to the cold tank to cool theelectrostatic chuck to a desired lower temperature. The heating andcooling system further includes at least one temporary storage tank forstoring the thermal transfer fluid for a duration when switching thetemperature (e.g., the thermal load) of the electrostatic chuck.

According to some embodiments, when it is desired to switch atemperature of the electrostatic chuck (e.g., switch (place) the thermalload of the electrostatic chuck from one of the hot tank or the coldtank to the other of the hot tank or the cold tank), circulation of theone of the hot thermal transfer fluid or the cold thermal transfer fluidto the electrostatic chuck is stopped and circulation of the other ofthe hot thermal transfer fluid or the cold thermal transfer fluid to theelectrostatic chuck begins. However, after switching the thermal load onthe electrostatic chuck, the thermal transfer fluid return piping isfilled with the previously circulated thermal transfer fluid (i.e., whenthe thermal load is switched from the hot tank to the cold tank, aportion of the hot thermal transfer fluid remains in the thermaltransfer fluid return piping; similarly, when the thermal load isswitched from the cold tank to the hot tank, a portion of the coldthermal transfer fluid remains in the thermal transfer fluid returnpiping). In other words, after switching the thermal load of theelectrostatic chuck, the thermal transfer fluid return piping includes asurge volume of the thermal transfer fluid, the thermal transfer fluidin the thermal transfer fluid return piping having an undesiredtemperature. The thermal transfer fluid remaining in the thermaltransfer fluid return piping immediately after switching the thermalload of the electrostatic chuck may be referred to herein as a “surgevolume” of thermal transfer fluid.

Since the temperature difference between the hot thermal transfer fluidand the cold thermal transfer fluid may be greater than about 50° C.(e.g., greater than about 100° C., greater than about 140° C., etc.), itis undesired to direct the surge volume of the thermal transfer fluid tothe tank from which the thermal transfer fluid is circulating to theelectrostatic chuck. Accordingly, in some embodiments, the surge volumeof the thermal transfer fluid in the thermal transfer fluid returnpiping is directed to a temporary tank substantially immediately afterswitching the thermal load of the electrostatic chuck from one of thehot tank or the cold tank to the other of the hot tank or the cold tank.After the temperature of the thermal transfer fluid in the thermaltransfer fluid return piping is within a predetermined range of thetemperature of the thermal transfer fluid currently circulating to theelectrostatic chuck, the circulating thermal transfer fluid in thethermal transfer fluid return piping is directed to the respective hottank or cold tank. After the thermal load is switched again, the thermaltransfer fluid in the temporary tank is directed to the hot tank or coldtank that is free of the thermal load from the electrostatic chuck(i.e., the hot tank or cold tank from which thermal transfer fluid isnot presently circulating to the electrostatic chuck).

Directing the surge volume of the thermal transfer fluid to thetemporary tank after switching the thermal load of the electrostaticchuck may facilitate improved temperature control of the electrostaticchuck. For example, the temperature of the electrostatic chuck may berepeatedly changed by as much as about 140° C. (e.g., as much as about160° C., as much as about 180° C., as much as about 200° C., as much asabout 250° C., or even as much as about 300° C.) without excessiveheating or cooling times (e.g., within less than about two minutes, suchas less than about one minute, or even within less than about 30seconds). By way of contrast, heating and cooling systems of etch toolsthat do not include the temporary tank and operate according to themethods described herein may exhibit undesired surges in temperature ofone or both of a hot tank or cold tank responsive to receiving a surgeof thermal transfer fluid having a substantially different temperature(e.g., more than about 50° C.) than a set-point of the electrostaticchuck and having a temperature substantially different than thetemperature of the thermal transfer fluid circulating to theelectrostatic chuck.

FIG. 1 is a simplified schematic of a tool 100, such as an etch tool.The tool 100 may be configured to facilitate processing of at least aportion of a semiconductor device from, for example, a semiconductorwafer 110. In some embodiments, the tool 100 comprises an etch chamber,such as a dry etch chamber. In other embodiments, the tool 100 comprisesa dry chamber, such as used in sublimation drying.

The tool 100 may include a chamber 102 (e.g., an etch chamber) whereinplasma is generated for patterning features on the semiconductor wafer110. The tool 100 may include a substrate (e.g., wafer) holder assembly105, shown in dashed lines in FIG. 1. The substrate holder assembly 105may include an electrostatic chuck 106 disposed on a pedestal 108. Thepedestal 108 may be configured to move up and down in the viewillustrated in FIG. 1 to adjust a height of the semiconductor wafer 110in the chamber 102.

In some embodiments, the electrostatic chuck 106 may comprise a lowerelectrode of the tool 100. The lower electrode may also be referred toas the cathode of the tool 100. The tool 100 may also include an upperelectrode 112. The upper electrode 112 may comprise, for example, a gasdistribution showerhead configured for distributing one or more gasesfrom a gas supply line 114. The gas distribution showerhead may includeapertures 116 for distributing the gas from the gas supply line 114 intothe chamber 102. Although FIG. 1 illustrates that the upper electrode112 and the gas distribution showerhead are the same, it is contemplatedthat in other embodiments, the tool 100 may include a gas distributionshowerhead that is separate from the upper electrode 112.

The upper electrode 112 may be electrically coupled to a power source118 for providing power to the upper electrode 112 (e.g., to the gasdistribution showerhead) for providing power to the gas supplied by thegas supply line 114 and generating a plasma in a region 104 between theupper electrode 112 and the semiconductor wafer 110. The power source118 may comprise a high frequency radio frequency (RF) power source, adirect current (DC) power source, or a combination of the two. As knownin the art, the power source 118 may be electrically coupled to, forexample, an inductive coil, for generating the radio frequency power.Adjustment of the frequency of the high frequency power source 118 mayalter an ion flux of the plasma generated by the upper electrode 112.The upper electrode 112 and the high frequency power source 118 may beelectrically connected to an electrical ground 120.

Plasma generated from the gas supply line 114 may be directed toward thesemiconductor wafer 110. The semiconductor wafer 110 may be biasedthrough the electrostatic chuck 106. The electrostatic chuck 106 may beconfigured to hold the semiconductor wafer 110 in place by applicationof RF power. The electrostatic chuck 106 may be electrically coupled toa power source 122 for generating a low radio frequency power to biasthe electrostatic chuck 106 and may be electrically connected to aground 124. The power source 122 may be electrically connected to theelectrostatic chuck 106 through a matching box 126. The matching box 126may be configured to cause the load impedance of the power source 122 tomatch an internal (or output) impedance thereof when plasma is generatedin the chamber 102. In some embodiments, application of a radiofrequency power source through the power source 122 may bias theelectrostatic chuck 106 relative to the plasma in the region 104 toadjust a bombardment energy of the plasma toward the semiconductor wafer110.

In some embodiments, the electrostatic chuck 106 may be electricallycoupled to a power source 128, which may comprise a direct current powersource or a high frequency radio frequency power source. In someembodiments, the power source 128 comprises a radio frequency powersource and may be configured to provide low frequency RF power, highfrequency RF power, or both to the electrostatic chuck 106. In someembodiments, the power source 128 is operably coupled to a matching box127 configured to cause the load impedance of the power source 128 tomatch an internal (or output) impedance thereof when plasma is generatedin the chamber 102. Application of power to the electrostatic chuck 106through the power source 128 may bias the semiconductor wafer 110 to theelectrostatic chuck 106 by electrostatic (e.g., Coulomb's) forces.

In FIG. 1, an edge ring, conductor ring, insulating materials around theelectrostatic chuck 106, and other components thereof are omitted forclarity.

In use and operation, an etching gas composition may be provided to thechamber 102 through the gas supply line 114 and the apertures 116 of thegas distribution showerhead. The plasma may be generated by applying ahigh frequency (e.g., a frequency between about 13 MHz and about 300MHz, such as between about 13.56 MHz and about 40.68 MHz, or a frequencyof about 60 MHz) to the upper electrode 112.

A vacuum pump 136 may be coupled to a gas discharge line 138 forremoving excess plasma and at least some reaction byproducts from thechamber 102. The vacuum pump 136 may be configured to control a pressureof the chamber 102 during the plasma etching process.

During processing (e.g., patterning) of the semiconductor wafer 110 toform, for example, one or more semiconductor devices, it may bedesirable to maintain a temperature of one or more components of thetool 100 (e.g., the electrostatic chuck 106) at one or more desiredtemperatures. For example, during some stages of processing, such asduring etching of the semiconductor wafer, it may be desired to maintaina relatively cold temperature (e.g., less than about 0° C., less thanabout −20° C., less than about −40° C., less than about −50° C., lessthan about −70° C., or less than about −100° C.) of at least onecomponent within the tool 100 and during other stages of processing,such as during other etching acts, during cleaning acts, or duringdeposition acts, it may be desired to maintain a relatively hottemperature (e.g., greater than about 20° C., greater than about 40° C.,greater than about 50° C., greater than about 70° C., or greater thanabout 100° C.) of the at least one component. Accordingly, over thecourse of processing of the semiconductor wafer 110, the semiconductorwafer 110 may repeatedly be exposed to cycles of relatively coldtemperatures and relatively hot temperatures. By way of nonlimitingexample, during some etching acts, it may be desirable to maintain thetemperature of the electrostatic chuck 106 and the semiconductor wafer110 as low as about −70° C. During cleaning of the tool 100 or duringother etching acts, it may be desirable to maintain a temperature of theelectrostatic chuck 106 and the semiconductor wafer 110 at a temperaturegreater than about 70° C. to facilitate sublimation of undesired etchbyproducts that accumulate proximate the electrostatic chuck 106 (e.g.,during dry cleaning of the tool 100).

Accordingly, in some embodiments, the electrostatic chuck 106 may beoperably connected to a heating and cooling apparatus (e.g., a chiller,a heat exchanger) 130 configured to maintain a desired temperature ofthe electrostatic chuck 106. The temperature of the semiconductor wafer110 may be maintained through thermal contact with the electrostaticchuck 106.

The heating and cooling apparatus 130 may include thermal transfer fluidsupply piping 132 that passes through the electrostatic chuck 106 andthermal transfer fluid return piping 134 for returning a thermaltransfer fluid to the heating and cooling apparatus 130. The thermaltransfer fluid may include a fluid formulated and configured to maintaina temperature of the electrostatic chuck. For example, the thermaltransfer fluid may be formulated to maintain a temperature of theelectrostatic chuck 106 less than about −20° C., less than about −40°C., less than about −50° C., less than about −70° C., less than about−100° C., or even less than about −150° C. The thermal transfer fluidmay also be formulated to maintain a temperature of the electrostaticchuck 106 greater than about 20° C., greater than about 40° C., greaterthan about 50° C., greater than about 70° C., greater than about 100°C., or even greater than about 150° C. Accordingly, the thermal transferfluid may exhibit an operating window as large as about 40° C., as largeas about 80° C., as large as about 100° C., as large as about 140° C.,as large as about 200° C., or even as large as about 300° C. In otherwords, a temperature difference between the thermal transfer fluid usedto maintain an elevated temperature of the electrostatic chuck 106 andthe thermal transfer fluid used to maintain a lower temperature of theelectrostatic chuck 106 may be as large as about 40° C., as large asabout 80° C., as large as about 100° C., as large as about 140° C., aslarge as about 200° C., or even as large as about 300° C.

In some embodiments, the thermal transfer fluid may exhibit a liquidtemperature range between at least about −70° C. and at least about 70°C., such as between about −100° C. and about 100° C. In someembodiments, a freezing point of the thermal transfer fluid may be lessthan about −70° C., less than about −80° C., less than about −90° C.,less than about −100° C., less than about −120° C., or even less thanabout −150° C. In some embodiments, a boiling point of the thermaltransfer fluid may be greater than about 70° C., greater than about 80°C., greater than about 90° C., greater than about 100° C., greater thanabout 120° C., or even greater than about 150° C.

In some embodiments, the thermal transfer fluid comprises afluorocarbon-based fluid, such as, for example, perfluorohexane (C₆F₁₄),perfluoro(2-butyl-tetrahydrofurane), another fluorocarbon, one or moreperfluorocarbons, one or more hydrofluoroethers (HFEs), one or moreperfluorocarbon ethers (PFEs), or combinations thereof. In otherembodiments, the thermal transfer fluid comprises a solution includingethylene glycol and water, a solution including propylene glycol andwater, a solution including methanol and water, one or more aliphatichydrocarbons (e.g., a polyalphaolefin (PAO)), a synthetic hydrocarbon(e.g., diethyl benzene (DEB), dibenzyl toluene, diaryl alkyl, partiallyhydrogenated terphenyl, etc.), a dimethyl phenyl-poly siloxane compound,a methyl phenyl-poly siloxane compound (also referred to as “siliconoil”), or combinations thereof.

FIG. 2 is a simplified schematic of the heating and cooling apparatus130, in accordance with some embodiments of the disclosure. The heatingand cooling apparatus 130 may include a cooling system 210 and a heatingsystem 230. Each of the cooling system 210 and the heating system 230may be in operable communication with a manifold 250 including valvingand piping for directing the thermal transfer fluid between theelectrostatic chuck 106 (FIG. 1) and each of the cooling system 210 andthe heating system 230.

The manifold 250 may be in operable communication with the thermaltransfer fluid supply piping 132 and the thermal transfer fluid returnpiping 134. As described with reference to FIG. 1, the thermal transferfluid supply piping 132 and the thermal transfer fluid return piping 134may be in operable communication with the electrostatic chuck 106 forcontrolling a temperature thereof.

The cooling system 210 may be configured to cool the thermal transferfluid to a desired temperature (e.g., about −70° C.). The cooling system210 may include, for example, a cold tank 212 configured to store thethermal transfer fluid. In some embodiments, the cold tank 212 mayinclude the thermal transfer fluid. The thermal transfer fluid in thecold tank 212 may be at a relatively low temperature (relative to atemperature of the thermal transfer fluid in a hot tank 232) and may,therefore, be referred to herein as a “cold thermal transfer fluid.” Thethermal transfer fluid in the cold tank 212 may be cooled with arefrigerant in a first heat exchanger 214, which may comprise, forexample, an evaporator. The refrigerant may pass from the first heatexchanger 214 to a compressor 216, from the compressor 216 to acondenser 218, and from the condenser to an expansion valve 220 tocomplete a refrigeration cycle. Accordingly, the cold thermal transferfluid from the cold tank 212 may be cooled with the refrigerant in therefrigeration cycle. Although the cold thermal transfer fluid is shownas being cooled by a particular refrigeration cycle, the disclosure isnot so limited and the cold thermal transfer fluid may be cooled byother means.

The cold thermal transfer fluid in the cold tank 212 may be in operablecommunication with a pump 222 configured to provide the cold thermaltransfer fluid to the manifold 250 and to the electrostatic chuck 106via the thermal transfer fluid supply piping 132. The cooling system 210may further include a temporary tank (also referred to herein as a“temporary storage tank”) 224 configured for storing a portion of thethermal transfer fluid of the heating and cooling system 130, as will bedescribed herein. A volume of the temporary tank 224 may be betweenabout 5.0% and about 20% a volume of the cold tank 212, such as betweenabout 5.0% and about 10%, between about 10.0% and about 15.0%, orbetween about 15.0% and about 20.0% a volume of the cold tank 212.

The cold tank 212 and the temporary tank 224 may be configured to be influid communication with the thermal transfer fluid return piping 134.The temporary tank 224 may be configured to be in fluid communicationwith the thermal transfer fluid return piping 134 via a valve 226. Thecold tank 212 may be configured to be in fluid communication with thethermal transfer fluid return piping 134 via a valve 227. As will beunderstood, operation of the valves 226, 227 may be used to direct theflow of thermal transfer fluid from the thermal transfer fluid returnpiping 134 to the cold tank 212 (e.g., through cold tank return piping211) or to the temporary tank 224 (e.g., through temporary tank returnpiping 223). In some embodiments, a first temperature indicator 228(e.g., temperature probe) may be located in the thermal transfer fluidreturn piping 134 and positioned to measure a temperature of the thermaltransfer fluid proximate each of the valves 226, 227. The heating andcooling system 130 may include a controller 270 in operablecommunication with the valves 226, 227 and the first temperatureindicator 228 and configured to open or close the valves 226, 227 basedon a temperature measured by the first temperature indicator 228, aswill be described herein.

Although FIG. 2 illustrates that the valves 226, 227 are separate anddistinct, it is understood that the thermal transfer fluid return piping134 may be configured to be placed in fluid communication with each ofthe cold tank return piping 211 and the temporary tank return piping 223with, for example, a three-way valve. In other words, the valves 226,227 may be replaced with a three-way valve.

The heating system 230 may be configured to heat the thermal transferfluid to a desired temperature (e.g., about 70° C.). The heating system230 may include, for example, a hot tank 232 configured to store thethermal transfer fluid. In some embodiments, the hot tank 232 mayinclude the thermal transfer fluid. A temperature of the thermaltransfer fluid in the hot tank 232 may be regulated with a second heatexchanger 242 or a cooler 244, depending on a desired temperature of thethermal transfer fluid in the hot tank 232. The thermal transfer fluidin the hot tank 232 may be at a relatively high temperature than thecold thermal transfer fluid in the cold tank 212 and may, therefore, bereferred to herein as a “hot thermal transfer fluid.” The second heatexchanger 242 may comprise, for example, an electric heater. In otherembodiments, the second heat exchanger 242 may comprise a shell and tubeheat exchanger including a heating fluid configured to provide thermalenergy to the hot thermal transfer fluid stored within the hot tank 232.In some embodiments, the cooler 244 may be configured to lower atemperature of the thermal transfer fluid in the hot tank 232.

The hot thermal transfer fluid in the hot tank 232 may be in operablecommunication with a pump 234 configured to provide the hot thermaltransfer fluid to the manifold 250 and to the electrostatic chuck 106via the thermal transfer fluid supply piping 132. The heating system 230may further include a temporary tank (also referring to herein as a“temporary storage tank”) 236 configured for storing a portion of thethermal transfer fluid from the thermal transfer fluid return piping134, as will be described herein. A volume of the temporary tank 236 maybe between about 5.0% and about 20% a volume of the hot tank 232, suchas between about 5.0% and about 10%, between about 10.0% and about15.0%, or between about 15.0% and about 20.0% a volume of the cold tank212.

The temporary tank 236 and the hot tank 232 may be configured to be inoperable communication with the thermal transfer fluid return piping134. The temporary tank 236 may be configured to be in fluidcommunication with the thermal transfer fluid return piping 134 via avalve 238 and the hot tank 232 may be configured to be in fluidcommunication with the thermal transfer fluid return piping 134 via avalve 239. As will be understood, operation of the valves 238, 239 maybe used to direct the flow of thermal transfer fluid from the thermaltransfer fluid return piping 134 to the hot tank 232 (e.g., through hottank return piping 231) or to the temporary tank 236 (e.g., throughtemporary tank return piping 235). In some embodiments, a secondtemperature indicator (e.g., temperature probe) 240 may be located inthe thermal transfer fluid return piping 134 and positioned to measure atemperature of the thermal transfer fluid proximate each of the valves238, 239. The controller 270 may be in operable communication with thevalves 238, 239 and configured to open or close the valves 238, 239based on a temperature measured by the second temperature indicator 240,as will be described herein. As will be described herein, the valves238, 239 may be configured to direct the thermal transfer fluid from thethermal transfer fluid return piping 134 to one of the temporary tank236 or the hot tank 232 based on a temperature measured by the secondtemperature indicator 240.

Although FIG. 2 illustrates that the valves 238, 239 are separate anddistinct, it is understood that the thermal transfer fluid return piping134 may be configured to be placed in fluid communication with each ofthe hot tank return piping 231 and the temporary tank return piping 235with, for example, a three-way valve.

Although FIG. 2 illustrates that the thermal transfer fluid returnpiping 134 includes the first temperature indicator 228 and the secondtemperature indicator 240, the disclosure is not so limited. In otherembodiments, a single temperature indicator may be located andpositioned in the thermal transfer fluid return piping 134 proximate ajunction where the thermal transfer fluid return piping 134 splitstoward the cooling system 210 and the heating system 230, as indicatedat junction 275. In some such embodiments, a volume of the thermaltransfer fluid return piping between the valves 226, 227 and thejunction 275 and a volume of the thermal transfer fluid return piping134 between the valves 238, 239 and the junction 275 may be less thanabout 10%, less than about 5%, or less than about 1% a total volume ofthe thermal transfer fluid return piping 134.

The first pump 222 and the second pump 234 may be configured to be influid communication with the thermal transfer fluid supply piping 132via respective valves 251, 252. The valves 251, 252 may be manipulatedto direct one of the cold thermal transfer fluid from the cold tank 212or the hot thermal transfer fluid from the hot tank 232 to theelectrostatic chuck 106 through the thermal transfer fluid supply piping132. For example, when it is desired to maintain an elevated temperatureof the electrostatic chuck 106, the valve 252 may be configured todirect the hot thermal transfer fluid from the hot tank 232 to theelectrostatic chuck 106 while the valve 251 is closed. When it isdesired to maintain a relatively lower temperature of the electrostaticchuck 106, valve 252 may be closed and the valve 251 may be opened todirect the cold thermal transfer fluid from the cold tank 212 to theelectrostatic chuck 106. Although FIG. 2 illustrates that the valves251, 252 are separate, the disclosure is not so limited. In otherembodiments, a three-way valve may be configured to place the cold tank212 in fluid communication with the thermal transfer fluid supply piping132 or the hot tank 232 in fluid communication with the thermal transferfluid supply piping 132.

In use and operation, when it is desired to maintain a relatively lowtemperature of the electrostatic chuck 106, the cold thermal transferfluid from the cold tank 212 is circulated to the thermal transfer fluidsupply piping 132 and to the electrostatic chuck 106. The cold thermaltransfer fluid exchanges heat with the electrostatic chuck 106 and isreturned to the cold tank 212 via the thermal transfer fluid returnpiping 134 and the cold tank return piping 211. While the cold thermaltransfer fluid is circulated from the cold tank 212, the hot thermaltransfer fluid in the hot tank 232 is uncirculated or is circulated in aseparate loop bypassing the electrostatic chuck 106. When it is desiredto heat the electrostatic chuck 106, circulation of the cold thermaltransfer fluid from the cold tank 212 is stopped (e.g., the flow of thecold thermal transfer fluid is stopped or circulation of the coldthermal transfer fluid through the electrostatic chuck 106 is stoppedand the cold thermal transfer fluid is circulated in a separate loopbypassing the electrostatic chuck 106) and the hot thermal transferfluid from the hot tank 232 is circulated to the electrostatic chuck 106and returned to the hot tank 232 via the thermal transfer fluid returnpiping 134 and the hot tank return piping 231.

During processing of a semiconductor wafer 110, the temperature of theelectrostatic chuck 106 may be changed rapidly and frequently, dependingon the particular process conditions within the tool 100. As describedabove, when the temperature requirements of the electrostatic chuck 106change, circulation of the thermal transfer fluid supplied to theelectrostatic chuck 106 is switched from one of the cooling system 210or the heating system 230 to the other of the cooling system 210 or theheating system 230. In conventional systems, when the circulation of thethermal transfer fluid is switched from one of the cold tank 212 or thehot tank 232 to the other of the cold tank 212 or the hot tank 232, thethermal transfer fluid in the thermal transfer fluid supply piping 132,the electrostatic chuck 106, and the thermal transfer fluid returnpiping 134 remains at the temperature from which the thermal load ischanged and is returned to the tank from which the thermal transferfluid is circulated. In other words, and as one example, whencirculation of the thermal transfer fluid changes from the cold tank 212to the hot tank 232, the cold thermal transfer fluid remaining in thethermal transfer fluid supply piping 132, the electrostatic chuck 106,and the thermal transfer fluid return piping 134 (e.g., a surge volumeof the thermal transfer fluid) is returned to the hot tank 232.

Where a temperature difference between the cold tank 212 and the hottank 232 is more than about, for example 50° C., such as more than about70° C., more than about 100° C., more than about 120° C., more thanabout 140° C., or even more than about 200° C., the surge volume ofthermal transfer fluid returned to the cold tank 212 or the hot tank 232responsive to switching the thermal load from the hot tank 232 or coldtank 212, respectively, when the thermal transfer load at theelectrostatic chuck 106 is switched may cause an undesired deviation inthe temperature of the thermal transfer fluid in the respective coldtank 212 or hot tank 232.

Accordingly, in some embodiments, the cooling system 210 includes thetemporary storage tank 224 and the heating system 230 includes thetemporary storage tank 236 configured to receive the surge volume ofthermal transfer fluid when the thermal load on the electrostatic chuck106 is switched. As will be described herein, in some embodiments, theheating and cooling apparatus 130 is configured to transfer thermaltransfer fluid stored in the temporary tank 224 to the cold tank 212when the thermal load from the electrostatic chuck 106 is on the heatingsystem 230. For example, temporary tank return piping 225 may beconfigured to place the temporary tank 224 in fluid communication withthe cold tank 212 via a valve 229. Similarly, the heating and coolingapparatus 130 may be configured to transfer the thermal transfer fluidfrom the temporary tank 236 to the hot tank 232 when the thermal loadfrom the electrostatic chuck 106 is on the cooling system 210. Forexample, temporary tank return piping 241 may be configured to place thetemporary tank 236 in fluid communication with the hot tank 232 via avalve 243.

FIG. 3 is a simplified flow diagram of a method 300 of operating theheating and cooling apparatus 130, in accordance with some embodimentsof the disclosure. The method 300 includes act 302 including circulatinga cold thermal transfer fluid from a cold tank to an electrostatic chuckand back to the cold tank through thermal transfer fluid return pipingto place a thermal load from the electrostatic chuck on the cold tank;act 304 including switching the thermal load from the electrostaticchuck from the cold tank to a hot tank by directing hot thermal transferfluid from the hot tank to the electrostatic chuck and to the thermaltransfer fluid return piping; act 306 including, after switching thethermal load from the cold tank to the hot tank, directing the coldthermal transfer fluid remaining in the thermal transfer fluid returnpiping to a temporary tank associated with the hot tank; act 308including, after a suitable transition time, directing the hot thermaltransfer fluid circulating from the hot tank back to the hot tank; act310 including switching the thermal load from the electrostatic chuckfrom the hot tank to the cold tank by directing the cold thermaltransfer fluid from the cold tank to the electrostatic chuck; act 312including directing the hot thermal transfer fluid in the thermaltransfer fluid return piping to a temporary storage tank associated withthe cold tank; act 314 including, after a suitable transition time,directing the cold thermal transfer fluid circulating from the cold tankback to the cold tank; act 316 including unloading the thermal transferfluid in the temporary tank associated with the hot tank to the hot tankwhile the thermal load from the electrostatic chuck is on the cold tank;act 318 including switching the thermal load from the electrostaticchuck from the cold tank to the hot tank by directing the hot thermaltransfer fluid from the hot tank to the electrostatic chuck; act 320including directing the cold thermal transfer fluid in the thermaltransfer fluid return piping to the temporary storage tank associatedwith the hot side; act 322 including, after a suitable transitionperiod, directing the hot thermal transfer fluid circulating from thehot tank back to the hot tank; act 324 including unloading the thermaltransfer fluid from the temporary tank associated with the cold tankwhile the thermal load from the electrostatic chuck is on the hot tank;and act 326 including repeating acts 310 through 324 a desired number oftimes.

With reference to FIG. 1 through FIG. 3, act 302 includes circulating acold thermal transfer fluid from a cold tank to an electrostatic chuckto place a thermal load from the electrostatic chuck on the cold tank.By way of example, and with reference to FIG. 2, act 302 may includecirculating the cold thermal transfer fluid from the cold tank 212 tothe electrostatic chuck 106 via the thermal transfer fluid supply piping132 and back to the cold tank 212 via the thermal transfer fluid returnpiping 134. The cold thermal transfer fluid may lower a temperature ofthe electrostatic chuck 106 during circulation thereof. While the coldthermal transfer fluid is circulated from the cold tank 212, the hotthermal transfer fluid in the hot tank 232 may not be circulated or maybe circulated in a closed loop wherein the electrostatic chuck 106 isbypassed.

Act 304 includes switching the thermal load from the electrostatic chuckfrom the cold tank to a hot tank by directing hot thermal transfer fluidfrom the hot tank to the electrostatic chuck and to the thermal transferfluid return piping. For example, circulation of the cold thermaltransfer fluid to the electrostatic chuck 106 from the cold tank 212 maybe stopped by closing the valve 251 in fluid communication with the coldtank 212 and opening the valve 252 in fluid communication with the hottank 232. Similarly, the valve 227 in fluid communication with a coldtank return piping 211 may be closed and the heating system 230 may beplaced in fluid communication with the thermal transfer fluid returnpiping 134. Accordingly, the hot thermal transfer fluid may becirculated from the hot tank 232 to the electrostatic chuck 106.Switching the thermal load from the electrostatic chuck 106 from thecold tank 212 to the hot tank 232 may include increasing the temperatureof the electrostatic chuck 106.

Act 306 includes, after switching the thermal load from the cold tank tothe hot tank, directing the cold thermal transfer fluid remaining in thethermal transfer fluid return piping to a temporary tank associated withthe hot tank. In some embodiments, act 306 may be performedsubstantially simultaneously or immediately after act 304. For example,after the thermal load from the electrostatic chuck 106 is switched fromthe cold tank 212 to the hot tank 232, the cold thermal transfer fluidthat was circulated during act 302 may remain in the thermal transferfluid supply piping 132, the electrostatic chuck 106, and the thermaltransfer fluid return piping 134. When the thermal load from theelectrostatic chuck 106 is switched from the cold tank 212 to the hottank 232, the hot thermal transfer fluid is circulated to theelectrostatic chuck 106 and the cold thermal transfer fluid remaining inthermal transfer fluid supply piping 132, the electrostatic chuck 106,and the thermal transfer fluid return piping 134 may be directed to thetemporary tank 236 until the temperature of the thermal transfer fluidin the thermal transfer fluid return piping 134 reaches a desiredtemperature (e.g., such that the cold thermal transfer fluid issubstantially flushed from the thermal transfer fluid return piping134).

Act 308 may include, after a suitable transition time, directing the hotthermal transfer fluid circulating from the hot tank back to the hottank. For example, after a sufficient duration, the hot thermal transferfluid in the thermal transfer fluid return piping 134 may be directed tothe hot tank 232 rather than to the temporary tank 236. In someembodiments, the valve 238 may be closed to stop a flow of the hotthermal transfer fluid to the temporary tank 236 and the valve 239 maybe opened to direct the flow of the hot thermal transfer fluid to thehot tank 232. In some embodiments, the valves 238, 239 may be inoperable communication with the temperature indicator 240 and thecontroller 270. In some such embodiments, the controller 270 may beconfigured to direct the hot thermal transfer fluid to the hot tank 232responsive to measuring a temperature of the hot thermal transfer fluidproximate the temperature indicator 240 greater than a predeterminedtemperature by manipulation of the valves 238, 239 (i.e., opening thevalve 239 and closing the valve 238). In other embodiments, if atemperature difference between the hot thermal transfer fluid in the hottank 232 and the hot thermal transfer fluid proximate the valves 238,239 is less than a predetermined value, the controller 270 may beconfigured to direct the hot thermal transfer fluid to the hot tank 232.By way of nonlimiting example, if the temperature difference between thehot thermal transfer fluid in the hot tank 232 and the hot thermaltransfer fluid in the thermal transfer fluid return piping 134 is lessthan about 10° C., less than about 5° C., or less than about 2° C., thevalve 239 may be opened and the valve 238 may be closed to direct thethermal transfer fluid to the hot tank 232 rather than to the temporarytank 236. In other embodiments, the controller 270 may be configured todirect the hot thermal transfer fluid in the thermal transfer fluidreturn piping 134 to the hot tank 232 after a predetermined durationafter which the thermal load from the electrostatic chuck 106 isswitched from the cold tank 212 to the hot tank 232. In someembodiments, the duration may be between about 1 second and about 5seconds, between about 5 seconds and about 10 seconds, between about 10seconds and about 20 seconds, or between about 20 seconds and about 30seconds. However, the disclosure is not so limited and the duration maybe greater depending on the length of the thermal transfer fluid supplypiping 132 and the thermal transfer fluid return piping 134.

Act 310 includes switching the thermal load from the electrostatic chuckfrom the hot tank to the cold tank by directing the cold thermaltransfer fluid from the cold tank to the electrostatic chuck. Switchingthe thermal load from the electrostatic chuck 106 from the hot tank 232to the cold tank 212 may include stopping circulation of the hot thermaltransfer fluid from the hot tank 232 to the electrostatic chuck 106 andcirculating the cold thermal transfer fluid from the cold tank 212 tothe electrostatic chuck 106. By way of nonlimiting example, circulationof the hot thermal transfer fluid to the electrostatic chuck 106 may bestopped by closing the valve 252 and opening the valve 251.

Act 312 includes directing the thermal transfer fluid in the thermaltransfer fluid return piping to a temporary storage tank associated withthe cold tank. In some embodiments, act 312 may be performedsubstantially simultaneously or immediately after act 310. For example,after the thermal load from the electrostatic chuck 106 is switched fromthe hot tank 232 to the cold tank 212, the hot thermal transfer fluidmay remain in the thermal transfer fluid supply piping 132, theelectrostatic chuck 106, and the thermal transfer fluid return piping134. When the cold thermal transfer fluid is circulated to theelectrostatic chuck 106, the hot thermal transfer fluid remaining in thethermal transfer fluid supply piping 132, the electrostatic chuck 106,and the thermal transfer fluid return piping 134 may be directed to thetemporary tank 224 for a duration until the temperature of the coldthermal transfer fluid in the thermal transfer fluid return piping 134reaches equilibrium (e.g., such that the hot thermal transfer fluid issubstantially flushed from the thermal transfer fluid return piping134).

Act 314 may include, after a suitable transition time, directing thecold thermal transfer fluid circulating from the cold tank back to thecold tank. For example, after a sufficient duration, the cold thermaltransfer fluid in the thermal transfer fluid return piping 134 may bedirected to the cold tank 212 rather than to the temporary tank 224. Insome embodiments, the valve 226 may be closed to stop a flow of the coldthermal transfer fluid to the temporary tank 224 and the valve 227 maybe opened to direct the flow of the cold thermal transfer fluid to thecold tank 212.

In some embodiments, the controller 270 may be in operable communicationwith the temperature indicator 228 and the valves 226, 227. In some suchembodiments, the controller 270 may be configured to open the valve 227and close the valve 226 (i.e., direct the cold thermal transfer fluid tothe cold tank 212) responsive to measuring a temperature of the coldthermal transfer fluid proximate the temperature indicator 228 less thana predetermined temperature. In other embodiments, if a temperaturedifference between the cold thermal transfer fluid in the cold tank 212and the cold thermal transfer fluid proximate the valves 226, 227 isless than a predetermined value, the controller 270 may be configured todirect the cold thermal transfer fluid to the cold tank 212. By way ofnonlimiting example, if the temperature difference is less than about10° C., less than about 5° C., or less than about 2° C., the controller270 may direct the thermal transfer fluid to the cold tank 212 ratherthan to the temporary tank 224. In other embodiments, the controller 270may be configured to direct the cold thermal transfer fluid in thethermal transfer fluid return piping 134 to the cold tank 212 after apredetermined duration after which the thermal load from theelectrostatic chuck 106 is switched from the hot side to the cold side.In some embodiments, the duration may be between about 1 second andabout 5 seconds, between about 5 seconds and about 10 seconds, betweenabout 10 seconds and about 20 seconds, or between about 20 seconds andabout 30 seconds. However, the disclosure is not so limited and theduration may be greater depending on the length of the thermal transferfluid supply piping 132 and the thermal transfer fluid return piping134.

Act 316 includes unloading the thermal transfer fluid in the temporarytank associated with the hot tank to the hot tank while the thermal loadfrom the electrostatic chuck is on the cold tank. In some embodiments,act 316 is performed substantially simultaneously with act 312, act 314,or both. The controller 270 may be in operable communication with thevalve 243 and configured to open the valve 243 when the thermal loadfrom the electrostatic chuck 106 is on the cold tank 212. In someembodiments, the valve 243 is opened and the thermal transfer fluid inthe temporary tank 236 is gravity fed to the hot tank 232. In otherembodiments, the thermal transfer fluid in the temporary tank 236 ispumped to the hot tank 232 in a controlled manner (e.g., 0.5 L/min, 1.0L/min, 2.0 L/min, etc.) such as through a flow restrictor. By way ofnonlimiting example, the thermal transfer fluid in the temporary tank236 may be removed from the temporary tank 236 over a predeterminedduration (e.g., 30 seconds, 1 minute, 2 minutes, etc.). Since thethermal load from the electrostatic chuck 106 is on the cold side of theheating and cooling apparatus 130 while the thermal transfer fluid inthe temporary tank 236 is flowed to the hot tank 232, the temperature ofthe electrostatic chuck 106 is not effected by the thermal transferfluid from the temporary tank 236 entering the hot tank 232.

Act 318 includes switching the thermal load from the electrostatic chuckfrom the cold tank to the hot tank by directing the hot thermal transferfluid from the hot tank to the electrostatic chuck. Switching thethermal load from the electrostatic chuck 106 from the cold tank 212 tothe hot tank 232 may include stopping circulation of the cold thermaltransfer fluid from the cold tank 212 to the electrostatic chuck 106 andcirculating the hot thermal transfer fluid from the hot tank 232 to theelectrostatic chuck 106 and may be substantially similar to act 304described above.

Act 320 includes directing the cold thermal transfer fluid in thethermal transfer fluid return piping to the temporary tank associatedwith the hot side. In some embodiments, act 320 may be substantiallysimilar to act 306 described above.

Act 322 includes, after a suitable transition period, directing the hotthermal transfer fluid circulating from the hot tank back to the hottank. In some embodiments, act 322 is substantially similar to act 308.

Act 324 includes unloading the thermal transfer fluid from the temporarytank associated with the cold tank while the thermal load from theelectrostatic chuck is on the hot tank. In some embodiments, act 324 isperformed substantially simultaneously with act 320, act 322, or both.By way of nonlimiting example, the thermal transfer fluid in thetemporary tank 224 may be transferred to the cold tank 212 by openingthe valve 229. The controller 270 may be configured to open the valve229 when the thermal load from the electrostatic chuck 106 is on the hottank 232. In some embodiments, the valve 229 is opened and the hotthermal transfer fluid in the temporary tank 224 is gravity fed to thecold tank 212. In other embodiments, the thermal transfer fluid ispumped to the cold tank 212 in a controlled manner (e.g., about 0.5L/min, about 1.0 L/min, about 2.0 L/min, etc.), such as through a flowrestrictor. In yet other embodiments, the thermal transfer fluid in thetemporary tank 224 is removed therefrom over a predetermined duration(e.g., about 30 seconds, about 1 minute, about 2 minutes, etc.). Sincethe thermal load from the electrostatic chuck 106 is on the hot side ofthe heating and cooling apparatus 130 while the thermal transfer fluidin the temporary tank 224 is flowed to the cold tank 212, thetemperature of the electrostatic chuck 106 is not effected by thethermal transfer fluid from the temporary tank 224 entering the coldtank 212.

Act 326 include repeating acts 310 through 324 a desired number oftimes. For example, acts 310 through 324 may be repeated until asemiconductor wafer is patterned and the tool 100 is cleaned.

Accordingly, the temporary tank 224 and the temporary tank 236 may beconfigured to store a thermal transfer fluid having a differenttemperature than the thermal transfer fluid of the respective cold tank212 and hot tank 232 to prevent a spike in a temperature of therespective cold thermal transfer fluid and hot thermal transfer fluid.When the thermal load on the electrostatic chuck 106 is on the coldside, the thermal transfer fluid from the temporary tank 236 may bedrained into the hot tank 232 and the temperature of the hot thermaltransfer fluid may be equilibrated (e.g., brought to a set point).Similarly, while the thermal load on the electrostatic chuck 106 is onthe hot side, the thermal transfer fluid in the temporary tank 224 maybe drained to the cold tank 212 and the temperature of the cold thermaltransfer fluid may be equilibrated. Since the thermal transfer fluid inthe thermal transfer fluid supply piping 132, the electrostatic chuck106, and the thermal transfer fluid return piping 134 is directed to oneof the temporary tanks 224, 236 responsive to switching the thermal loadfrom one of the cold tank 212 or the hot tank 232 to the other of thecold tank 212 or the hot tank 232, the heating and cooling apparatus 130may be configured to maintain a desired temperature of the cold thermaltransfer fluid in the cold tank 212 and the hot thermal transfer fluidin the hot tank 232 in less than a predetermined time, such as less thanabout 2 minutes, less than about 1 minute, or even less than about 30seconds.

Although FIG. 1 through FIG. 3 have been described and illustrated asincluding the electrostatic chuck 106 and the thermal load has beendescribed in terms of the electrostatic chuck 106, the disclosure is notso limited. It will be understood that the thermal load may be placed ona platform to be heated and cooled and the thermal transfer fluid may becirculated through the platform.

FIG. 4 is a simplified schematic of a heating and cooling system 130′ inaccordance with other embodiments of the disclosure. The heating andcooling system 130′ may be substantially similar to the heating andcooling system 130 described above with reference to FIG. 2, except thatthe heating and cooling system 130′ may not include a separate temporarytank for each of the cooling system 210 and the heating system 230.Rather, the heating and cooling system 130′ may include a commontemporary tank 260 which may be configured to be in fluid communicationwith each of the cold tank 212 and the hot tank 232. The commontemporary tank 260 may be configured to receive the thermal transferfluid located in the thermal transfer fluid supply piping 132, thethermal transfer fluid return piping 134, and the electrostatic chuck106 after switching the thermal load on the electrostatic chuck 106 fromone of the cooling system 210 and the heating system 230 to the other ofthe cooling system 210 and the heating system 230. The common temporarytank 260 may be configured to be in fluid communication with the coldtank 212 and with the hot tank 232. A valve 262 may be configured todirect a flow from the temporary tank 260 to the cold tank 212 when openand stop such a flow when closed. A valve 264 may be configured todirect a flow from the temporary tank 260 to the hot tank 232 whenopened and stop such a flow when closed.

FIG. 5 is a simplified flow diagram of a method 500 of operating theheating and cooling apparatus 130′, in accordance with some embodimentsof the disclosure. The method 500 may include act 502 includingcirculating a cold thermal transfer fluid from a cold tank to anelectrostatic chuck and back to the cold tank through thermal transferfluid return piping to place a thermal load from the electrostatic chuckon the cold tank; act 504 including switching the thermal load from theelectrostatic chuck from the cold tank to a hot tank by directed hotthermal transfer fluid from the hot tank to the electrostatic chuck andto the thermal transfer fluid return piping; act 506 including, afterswitching the thermal load from the cold tank to the hot tank, directingthe cold thermal transfer fluid remaining in the thermal transfer fluidreturn piping to a temporary tank; act 508 including, after a suitabletransition time, directing the hot thermal transfer fluid circulatingfrom the hot tank back to the hot tank; act 510 including, while the hotthermal transfer fluid is circulating to and from the hot tank, drainingthe thermal transfer fluid from the temporary tank to the cold tank; act512 including switching the thermal load of the electrostatic chuck fromthe hot tank to the cold tank by directing the cold thermal transferfluid from the cold tank to the electrostatic chuck; act 514 including,after switching the thermal load from the hot tank to the cold tank,directing the hot thermal transfer fluid in the thermal transfer fluidreturn piping to the temporary tank; act 516 including, after a suitabletransition time, directing the cold thermal transfer fluid circulatingfrom the cold tank back to the cold tank; act 518 including, while thecold thermal transfer fluid is circulating to and from the cold tank,draining the thermal transfer fluid from the temporary tank to the hottank; and act 520 including repeating acts 504 through 518 a desirednumber of times.

With reference to FIG. 4 and FIG. 5, act 502 includes circulating a coldthermal transfer fluid from a cold tank to an electrostatic chuck andback to the cold tank through thermal transfer fluid return piping toplace a thermal load from the electrostatic chuck on the cold tank. Act502 may be substantially similar to act 302 described above withreference to FIG. 3. During act 502, there is no thermal load from theelectrostatic chuck 106 on the hot side.

Act 504 includes switching the thermal load from the electrostatic chuckfrom the cold tank to a hot tank by directing hot thermal transfer fluidfrom the hot tank to the electrostatic chuck and to the thermal transferfluid return piping. Act 504 may be substantially similar to act 304described above with reference to FIG. 3.

Act 506 includes after switching the thermal load from the electrostaticchuck from the cold tank to the hot tank, directing the cold thermaltransfer fluid remaining in the thermal transfer fluid return piping toa temporary tank. For example, after switching the thermal load of theelectrostatic chuck 106 from the cold tank 212 to the hot tank 232, thethermal transfer fluid supply piping 132, the electrostatic chuck 106,and the thermal transfer fluid return piping 134 may be filled with thecold thermal transfer fluid. The cold thermal transfer fluid in suchpiping may be directed to the temporary tank 260 for a predeterminedduration during an initial period of circulation of the hot thermaltransfer fluid. By way of nonlimiting example, the valve 238 may beopened and the valve 239 may be closed to direct the thermal transferfluid in the thermal transfer fluid return piping 134 to the temporarytank 260. The temporary tank 260 may be at least partially filled withthe cold thermal transfer fluid during act 506.

Act 508 includes, after a suitable transition time, directing the hotthermal transfer fluid circulating from the hot tank back to the hottank. By way of nonlimiting example, the valve 239 may be opened and thevalve 238 may be closed to direct the fluid in the thermal transferfluid return piping 134 to the hot tank 232.

In some embodiments, the valve 238 and the valve 239 may be in operablecommunication with the temperature indicator 240 and with the controller270. In some such embodiments, the controller 270 may be configured todirect the hot thermal transfer fluid to the hot tank 232 (i.e., openthe valve 239) responsive to measuring a temperature of the hot thermaltransfer fluid proximate the temperature indicator 240 greater than apredetermined temperature. In other embodiments, if a temperaturedifference between the hot thermal transfer fluid in the hot tank 232and the hot thermal transfer fluid measured by the temperature indicator240 is less than a predetermined value, the controller 270 may beconfigured to open the valve 239 to direct the hot thermal transferfluid to the hot tank 232. By way of nonlimiting example, if thetemperature difference is less than about 10° C., less than about 5° C.,or less than about 2° C., the controller 270 may direct the hot thermaltransfer fluid to the hot tank 232 rather than to the temporary tank260. In other embodiments, the controller 270 may be configured todirect the hot thermal transfer fluid in the thermal transfer fluidreturn piping 134 to the hot tank 232 after a predetermined durationafter which the thermal load from the electrostatic chuck 106 isswitched from the cold side to the hot side. In some embodiments, theduration may be between 1 second and about 5 seconds, between about 5seconds and about 10 seconds, between about 10 seconds and about 20seconds, or between about 20 seconds and about 30 seconds. However, thedisclosure is not so limited and the duration may be greater dependingon the length of the thermal transfer fluid supply piping 132 and thethermal transfer fluid return piping 134.

Act 510 includes while the hot thermal transfer fluid is circulated toand from the hot tank, draining the thermal transfer fluid from thetemporary tank to the cold tank. After the hot thermal transfer fluid isdirected to the hot tank 232 and the temporary tank 260 is out of fluidcommunication with the thermal transfer fluid return piping 134, thevalve 262 may be opened to direct the cold thermal transfer fluid in thetemporary tank 260 to the cold tank 212. In some embodiments, the coldthermal transfer fluid in the temporary tank 260 is gravity fed to thecold tank 212. In other embodiments, the cold thermal transfer fluid ispumped to the cold tank 212 in a controlled manner (e.g., about 0.5L/min, about 1.0 L/min, about 2.0 L/min, etc.), such as through a flowrestrictor. In yet other embodiments, the cold thermal transfer fluid inthe temporary tank 260 is removed therefrom over a predeterminedduration (e.g., about 30 seconds, about 1 minute, about 2 minutes,etc.). Since the thermal load from the electrostatic chuck 106 is on thehot side of the heating and cooling apparatus 130 while the cold thermaltransfer fluid in the temporary tank 260 is flowed to the cold tank 212,the temperature of the electrostatic chuck 106 is not effected by thecold thermal transfer fluid from the temporary tank 260 entering thecold tank 212 and the tank from which the thermal transfer fluid iscirculating to the electrostatic chuck 106 is not affected. The coldthermal transfer fluid from the temporary tank 260 may be substantiallycompletely removed from the temporary tank 260.

Act 512 includes switching the thermal load of the electrostatic chuckfrom the hot tank to the cold tank by directing the cold thermaltransfer fluid from the cold tank to the electrostatic chuck. In someembodiments, act 512 is substantially similar to act 310 described abovewith reference to FIG. 3.

Act 514 includes, after switching the thermal load from hot tank to thecold tank, directing the hot thermal transfer fluid in the thermaltransfer fluid return piping to the temporary tank. For example, afterswitching the thermal load of the electrostatic chuck 106 from the hottank 232 to the cold tank 212, the thermal transfer fluid supply piping132, the electrostatic chuck 106, and the thermal transfer fluid returnpiping 134 may be filled with the hot thermal transfer fluid. The hotthermal transfer fluid in such piping may be directed to the temporarytank 260 for a predetermined duration during an initial period ofcirculation of the cold thermal transfer fluid. By way of nonlimitingexample, the valve 226 may be opened and the valve 227 may be closed todirect the fluid in the thermal transfer fluid return piping 134 to thetemporary tank 260. The temporary tank 260 may be at least partiallyfilled with the hot thermal transfer fluid during act 514.

Act 516 includes, after a suitable transition time, directing the coldthermal transfer fluid circulating from the cold tank back to the coldtank. By way of nonlimiting example, the valve 226 may be closed and thevalve 227 may be opened to direct the cold thermal transfer fluid in thethermal transfer fluid return piping 134 to the cold tank 212.

In some embodiments, the valve 226 and the valve 227 may be in operablecommunication with the controller 270. In some such embodiments, thecontroller 270 may be configured to direct the cold thermal transferfluid to the cold tank 212 (i.e., open the valve 227) responsive tomeasuring a temperature of the cold thermal transfer fluid proximate thetemperature indicator 228 greater than a predetermined temperature. Inother embodiments, if a temperature difference between the cold thermaltransfer fluid in the cold tank 212 and the cold thermal transfer fluidmeasured by the temperature indicator 228 is less than a predeterminedvalue, the controller 270 may be configured to open the valve 227 todirect the cold thermal transfer fluid to the cold tank 212. By way ofnonlimiting example, if the temperature difference is less than about10° C., less than about 5° C., or less than about 2° C., the controller270 may be configured to direct the cold thermal transfer fluid to thecold tank 212 rather than to the temporary tank 260. In otherembodiments, the controller 270 may be configured to direct the coldthermal transfer fluid in the thermal transfer fluid return piping 134to the cold tank 212 after a predetermined duration after which thethermal load from the electrostatic chuck 106 is switched from the hotside to the cold side. In some embodiments, the duration may be betweenabout 1 second and about 5 seconds, between about 5 seconds and about 10seconds, between about 10 seconds and about 20 seconds, or between about20 seconds and about 30 seconds. However, the disclosure is not solimited and the duration may be greater depending on the length of thethermal transfer fluid supply piping 132 and the thermal transfer fluidreturn piping 134.

Act 518 includes, while the cold thermal transfer fluid is circulatingto and from the cold tank, draining the thermal transfer fluid in thetemporary tank to the hot tank. After the cold thermal transfer fluid isdirected to the cold tank 212 and the temporary tank 260 is out of fluidcommunication with the thermal transfer fluid return piping 134, thevalve 264 may be opened to direct the hot thermal transfer fluid in thetemporary tank to the hot tank 232. In some embodiments, the hot thermaltransfer fluid in the temporary tank 260 is gravity fed to the hot tank232. In other embodiments, the hot thermal transfer fluid is pumped tothe hot tank 232 in a controlled manner (e.g., about 0.5 L/min, about1.0 L/min, about 2.0 L/min, etc.), such as through a flow restrictor. Inyet other embodiments, the hot thermal transfer fluid in the temporarytank is removed therefrom over a predetermined duration (e.g., about 30seconds, about 1 minute, about 2 minutes, etc.). Since the thermal loadfrom the electrostatic chuck 106 is on the cold tank 212 while the hotthermal transfer fluid in the temporary tank 260 is flowed to the hottank 232, the temperature of the electrostatic chuck 106 is not effectedby the hot thermal transfer fluid in the temporary tank 260 entering thehot tank 232 from which the thermal transfer fluid is circulating to theelectrostatic chuck 106 is not affected. The hot thermal transfer fluidfrom the temporary tank 260 may be substantially completely removed fromthe temporary tank.

Act 520 includes repeating acts 504 through 518 a desired number oftimes. For example, acts 504 through 518 may be repeated until asemiconductor wafer is patterned and the tool 100 is cleaned.

Accordingly, a temperature of the electrostatic chuck 106 may bemaintained without large temperature swings in the temperature of thecold tank 212 or the hot tank 232 since surge volumes of thermaltransfer fluid having a substantially different temperature than thetemperature of the thermal transfer fluid in the cold tank 212 or thehot tank 232 are not placed on such tanks. In addition, since the surgevolume of the thermal transfer fluid is stored in a temporary tank andunloaded to the cold tank 212 or the hot tank 232 while the thermal loadis away from such cold tank 212 or hot tank 232, the respective tanksmay not exhibit a surge in temperature while the thermal load is placedthereon, increasing the effectiveness of the thermal transfer with theelectrostatic chuck 106.

Although FIG. 1 through FIG. 5 have been described as controlling thetemperature of the electrostatic chuck 106 during etching and cleaningacts, the disclosure is not so limited. In other embodiments, thetemperature of a chamber may be controlled according to the methodsdescribed herein in any process in which it is desired to control atemperature of the chamber between at least two temperatures having atemperature difference greater than, for example, about 50° C. in arelatively short duration. By way of nonlimiting example, the methodsdescribed above (e.g., the method 300 and the method 500) may be usedfor sublimation drying after wet cleaning (e.g., exposing thesemiconductor wafer 110 to, for example, a RCA cleaning process). Insome such embodiments, the thermal load from the electrostatic chuck 106may be on the cold tank 212 during sublimation drying and the thermalload from the electrostatic chuck 106 may be on the hot tank 232 duringwet cleaning.

Accordingly, in some embodiments, a system for processing asemiconductor device structure comprises a tool comprising a chamber anda platform within the chamber configured to receive a semiconductordevice structure thereon. The tool further comprises a heating andcooling system in operable communication with the platform andconfigured to control a temperature of the platform, the heating andcooling system comprising a cooling system including a cold tankconfigured to hold a cold thermal transfer fluid, the cold tankconfigured to be in fluid communication with the platform, thermaltransfer fluid supply piping, and thermal transfer fluid return piping,a heating system including a hot tank configured to hold a hot thermaltransfer fluid having a higher temperature than the cold thermaltransfer fluid, the hot tank configured to be in fluid communicationwith the platform, the thermal transfer fluid supply piping, and thethermal transfer fluid return piping, and at least one temporary tankconfigured to receive at least some of the cold thermal transfer fluidor the hot thermal transfer fluid from at least the thermal transferfluid return piping responsive to switching a thermal load of theplatform from one of the cooling system or the heating system to theother of the cooling system or the heating system.

Accordingly, in at least some other embodiments, a system fortemperature modification for use with a tool for processing asemiconductor device structure comprises a heating and cooling systemconfigured for operable communication with a platform of a processingtool, the heating and cooling system comprising a cold tank defining avolume configured to hold a cold thermal transfer fluid, the cold tankconfigured to be in fluid communication with the platform, a hot tankdefining a volume configured to hold a hot thermal transfer fluid, thecold tank configured to be in fluid communication with the platform andthermal transfer fluid return piping configured for fluid communicationwith each of the platform, the cold tank, the hot tank, a firsttemporary tank configured to be in fluid communication with the coldtank, and a second temporary tank configured to be in fluidcommunication with the hot tank.

Accordingly, in some embodiments, a method of operating a tool forprocessing a semiconductor device structure comprises switching athermal load of a platform of a tool from a cold tank of a heating andcooling apparatus to a hot tank thereof, a cold thermal transfer fluidremaining in thermal transfer fluid piping between the cold tank and theplatform, directing the cold thermal transfer fluid remaining in thethermal transfer fluid return piping to a temporary tank in fluidcommunication with the hot tank while directing a hot thermal transferfluid from the hot tank to the platform and from the platform to thethermal transfer fluid return piping, directing the hot thermal transferfluid from the thermal transfer fluid return piping to the hot tank,switching the thermal load of the platform from the hot tank to the coldtank, directing the hot thermal transfer fluid remaining in the thermaltransfer fluid return piping to a temporary tank in fluid communicationwith the cold tank while directing the cold thermal transfer fluid fromthe cold tank to the platform and from the platform to the thermaltransfer fluid return piping, and directing the cold thermal transferfluid from the thermal transfer fluid return piping to the cold tank.

While certain illustrative embodiments have been described in connectionwith the figures, those of ordinary skill in the art will recognize andappreciate that embodiments encompassed by the disclosure are notlimited to those embodiments explicitly shown and described herein.Rather, many additions, deletions, and modifications to the embodimentsdescribed herein may be made without departing from the scope ofembodiments encompassed by the disclosure, such as those hereinafterclaimed, including legal equivalents. In addition, features from onedisclosed embodiment may be combined with features of another disclosedembodiment while still being encompassed within the scope of thedisclosure.

What is claimed is:
 1. A system for processing one or more semiconductordevices, the system comprising: a tool comprising: a chamber; and aplatform within the chamber configured to receive one or moresemiconductor devices thereon; and a temperature control system inoperable communication with the platform and configured to control atemperature of the platform, the temperature control system comprising:a first tank configured to hold a thermal transfer fluid, the first tankconfigured to be in fluid communication with the platform and thermaltransfer fluid piping; a second tank configured to hold the thermaltransfer fluid at a different temperature than the thermal transferfluid in the first tank, the second tank configured to be in fluidcommunication with the platform and the thermal transfer fluid piping;and a temporary tank in direct fluid communication with the thermaltransfer fluid piping and configured to receive and store at least someof the thermal transfer fluid directly from the thermal transfer fluidpiping prior to the first tank or the second tank responsive toswitching a thermal load of the platform from one of the first tank orthe second tank to the other of the first tank or the second tank. 2.The system of claim 1, wherein the thermal transfer fluid pipingcomprises a junction, a first portion of the thermal transfer fluidpiping in fluid communication with the first tank downstream of thejunction and a second portion of the thermal transfer fluid piping influid communication with the second tank downstream of the junction. 3.The system of claim 2, wherein the temporary tank is located downstreamof the junction.
 4. The system of claim 1, further comprising anadditional temporary tank in direct fluid communication with the thermaltransfer fluid piping, wherein: the temporary tank is between the firsttank and the thermal transfer fluid piping; and the additional temporarytank is between the second tank and the thermal transfer fluid piping.5. The system of claim 1, wherein the thermal transfer fluid within thefirst tank comprises the same material composition as the thermaltransfer fluid within the second tank.
 6. The system of claim 1, furthercomprising: a first valve between the thermal transfer fluid piping andthe first tank; and a second valve between the thermal transfer fluidpiping and the temporary tank, the first valve and the second valveconfigured to selectively direct the thermal transfer fluid from thethermal transfer fluid piping to the temporary tank and the first tank.7. The system of claim 1, wherein the second tank is configured maintaina temperature of the thermal transfer fluid about 100° C. than the firsttank.
 8. The system of claim 1, wherein a volume of the temporary tankis between about 5% and about 20% of a volume of the first tank.
 9. Thesystem of claim 1, further comprising a condenser in operablecommunication with the first tank.
 10. A method of operating a tool forprocessing one or more semiconductor devices, the method comprising:switching a thermal load of a platform of a tool from a first tank to asecond tank, thermal transfer fluid remaining in thermal transfer fluidpiping between the first tank and the platform, the first tank defininga first volume configured to hold the thermal transfer fluid at a firsttemperature and the second tank defining a second volume configured tohold the thermal transfer fluid at a second temperature; after switchingthe thermal load of the platform from the first tank to the second tank,directing the thermal transfer fluid remaining in the thermal transferfluid piping to a temporary tank in fluid communication with the secondtank while directing the thermal transfer fluid from the second tank tothe platform and from the platform to the thermal transfer fluid piping;and after a duration, directing the thermal transfer fluid from thethermal transfer fluid piping directly to the second tank.
 11. Themethod of claim 10, further comprising: switching the thermal load ofthe platform from the second tank to the first tank; and after switchingthe thermal load of the platform from the second tank to the first tank,directing the thermal transfer fluid remaining in the thermal transferfluid piping to an additional temporary tank in fluid communication withthe first tank while directing thermal transfer fluid from the firsttank to the platform and from the platform to the thermal transfer fluidpiping.
 12. The method of claim 11, further comprising directing thethermal transfer fluid from the thermal transfer fluid piping to thefirst tank after directing the thermal transfer fluid remaining in thethermal transfer fluid piping to the additional temporary tank in fluidcommunication with the first tank while directing thermal transfer fluidfrom the second tank to the platform and from the platform to thethermal transfer fluid piping.
 13. The method of claim 10, whereinswitching a thermal load of a platform of a tool from a first tank to asecond tank comprises switching a thermal load of an electrostatic chuckof a tool for patterning a semiconductor wafer.
 14. The method of claim10, wherein directing the thermal transfer fluid remaining in thethermal transfer fluid piping to a temporary tank in fluid communicationwith the second tank while directing the thermal transfer fluid from thesecond tank to the platform and from the platform to the thermaltransfer fluid piping comprises opening a valve connecting the thermaltransfer fluid piping to the temporary tank.
 15. The method of claim 10,wherein directing the thermal transfer fluid remaining in the thermaltransfer fluid piping to a temporary tank in fluid communication withthe second tank comprises directing the thermal transfer fluid in thethermal transfer fluid piping directly to the temporary tank withoutdirecting the thermal transfer fluid from the thermal transfer fluidpiping to the second tank.
 16. The method of claim 10, wherein directingthe thermal transfer fluid remaining in the thermal transfer fluidpiping to a temporary tank in fluid communication with the second tankcomprises: measuring a temperature of the thermal transfer fluid in thethermal transfer fluid piping; and responsive to detecting a differencebetween the temperature of the thermal transfer fluid in the thermaltransfer fluid piping and a temperature of the thermal transfer fluid inthe second tank being less than about 10° C., directing the thermaltransfer fluid to the second tank.
 17. A system, comprising: a tankdefining a volume configured to hold a thermal transfer fluid at a firsttemperature, the tank configured to be in fluid communication with aplatform of a processing tool; an additional tank defining an additionalvolume configured to hold the thermal transfer fluid at a secondtemperature, the additional tank configured to be in fluid communicationwith the platform; and thermal transfer fluid piping between theplatform and each of the tank and the additional tank; and a temporarytank directly between the thermal transfer fluid piping and configuredto be in fluid communication with the tank and store the thermaltransfer fluid from the thermal transfer fluid piping for a durationresponsive to switching a thermal load of the platform from theadditional tank to the tank.
 18. The system of claim 17, wherein thethermal transfer fluid piping is in fluid communication with each of:tank return piping; temporary tank return piping; additional tank returnpiping; and valves configured to selectively direct a flow of thethermal transfer fluid from the thermal transfer fluid piping to thetank return piping, the temporary tank return piping, and the additionaltank return piping.
 19. The system of claim 17, further comprisingtemporary tank piping coupling the temporary tank to the thermaltransfer fluid piping.
 20. The system of claim 19, further comprisingtank return piping directly coupling the thermal transfer fluid pipingto the tank.